According to state law, Minnesota’s governor is authorized to fill the vacancy if a senator resigns. The governor, Democrat Mark Dayton, can make temporary appointments to fill Senate vacancies, but a special election must be held to fill the seat until the next scheduled election of that seat is held.

When would a special election be held in this case?

In Minnesota, if the seat is vacated at least 11 weeks before a scheduled primary, then a special election must be held the following November. There is a primary set for Aug. 14, 2018, in Minnesota, so that would mean that a special election would have to be held in November 2018 if Franken resigns before May 29, 2018. Minnesota’s other senator, Amy Klobuchar, (D), is up for re-election in that election.

The winner of the special election would serve out Franken’s term, which ends in January 2021. If that person wants to stay in the seat for the six-year term that begins in January 2021, he or she would have to face re-election in November 2020.